Fixes: NULL pointer dereference Fixes: 22381/clusterfuzz-testcase-minimized-ffmpeg_AV_CODEC_ID_NOTCHLC_fuzzer-5659879921680384.fuzz Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/projects/ffmpeg Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
		
			
				
	
	
		
			93 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			93 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * lzf decompression algorithm
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|  * Copyright (c) 2015 Luca Barbato
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|  *
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|  * This file is part of FFmpeg.
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|  *
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|  * FFmpeg is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU Lesser General Public
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|  * License as published by the Free Software Foundation; either
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|  * version 2.1 of the License, or (at your option) any later version.
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|  *
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|  * FFmpeg is distributed in the hope that it will be useful,
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|  * but WITHOUT ANY WARRANTY; without even the implied warranty of
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|  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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|  * Lesser General Public License for more details.
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|  *
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|  * You should have received a copy of the GNU Lesser General Public
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|  * License along with FFmpeg; if not, write to the Free Software
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|  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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|  */
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| 
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| /**
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|  * @file
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|  * lzf decompression
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|  *
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|  * LZF is a fast compression/decompression algorithm that takes very little
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|  * code space and working memory, ideal for real-time and block compression.
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|  *
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|  * https://en.wikibooks.org/wiki/Data_Compression/Dictionary_compression#LZF
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|  */
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| 
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| #include "libavutil/mem.h"
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| 
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| #include "bytestream.h"
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| #include "lzf.h"
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| 
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| #define LZF_LITERAL_MAX (1 << 5)
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| #define LZF_LONG_BACKREF 7 + 2
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| 
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| int ff_lzf_uncompress(GetByteContext *gb, uint8_t **buf, int64_t *size)
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| {
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|     int ret     = 0;
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|     uint8_t *p  = *buf;
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|     int64_t len = 0;
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| 
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|     while (bytestream2_get_bytes_left(gb) > 2) {
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|         uint8_t s = bytestream2_get_byte(gb);
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| 
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|         if (s < LZF_LITERAL_MAX) {
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|             s++;
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|             if (s > *size - len) {
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|                 *size += s + *size /2;
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|                 ret = av_reallocp(buf, *size);
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|                 if (ret < 0)
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|                     return ret;
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|                 p = *buf + len;
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|             }
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| 
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|             bytestream2_get_buffer(gb, p, s);
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|             p   += s;
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|             len += s;
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|         } else {
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|             int l   = 2 + (s >> 5);
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|             int off = ((s & 0x1f) << 8) + 1;
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| 
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|             if (l == LZF_LONG_BACKREF)
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|                 l += bytestream2_get_byte(gb);
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| 
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|             off += bytestream2_get_byte(gb);
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| 
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|             if (off > len)
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|                 return AVERROR_INVALIDDATA;
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| 
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|             if (l > *size - len) {
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|                 *size += l + *size / 2;
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|                 ret = av_reallocp(buf, *size);
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|                 if (ret < 0)
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|                     return ret;
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|                 p = *buf + len;
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|             }
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| 
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|             av_memcpy_backptr(p, off, l);
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| 
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|             p   += l;
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|             len += l;
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|         }
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|     }
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| 
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|     *size = len;
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| 
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|     return 0;
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| }
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